Introductory Chemistry, 5e (Tro)
Chapter 4 Atoms and Elements
True/False Questions
1) The smell of the ocean is caused by atoms.
2) The atom is the fundamental building block of everything we hear, feel, see, and experience.
3) An atom is the smallest identifiable unit of a compound.
4) John Dalton was the first person recorded as thinking that matter was ultimately composed of
atoms.
5) John Dalton formalized an atomic theory that gained acceptance in the early 19th century.
6) You can continually divide matter into smaller and smaller pieces without ever coming to an
end.
7) The plum pudding model proposed that negatively charged electrons were held in a sphere of
positive charge.
8) All of the positive charge of an atom is concentrated in the nucleus.
9) J.J. Thomson discovered the existence of protons.
10) Ernest Rutherford proved the existence of electrons.
11) The gold foil experiment proved that large regions of the atoms consisted of empty space.
12) The nucleus of an atom is a very small, dense region that contains over 99.9% of the atomic
mass.
13) Protons and electrons each have a mass of 1 amu.
14) A positive charge attracts negative charges and repels other positive charges.
15) The mass of a proton is exactly the same as the mass of a neutron.
16) The charges on electrons and neutrons cancel each other to give neutral atoms.
17) Protons and neutrons have similar masses and similar electrical charges.
18) An atom containing 8 protons, 9 neutrons, and 8 electrons would be considered charge-
neutral.
19) The number of protons in an atom’s nucleus defines the element.
20) If two atoms each contain different numbers of protons, the atoms must be from different
elements.
21) All elemental symbols are comprised of a two-letter abbreviation.
22) The elemental symbol for manganese is Mg.
23) All carbon atoms have exactly 6 protons.
24) The atomic number of nitrogen is 14.01.
25) Mendeleev is best remembered for his pioneering work on determining atomic structure.
26) Mendeleev’s early periodic table predicted the existence of elements that had yet to be
discovered.
27) In the modern periodic table, elements are listed in order of increasing atomic number rather
than increasing relative mass.
28) Metals are located on the left side of the periodic table.
29) The elements within a group on the periodic table tend to have similar properties.
30) Group 2A elements are called alkali metals.
31) Aluminum is one of the most commonly used metalloids.
32) An element is discovered that is a solid, has one valence electron, and readily forms a 1+ ion.
This element would be correctly classified as a nonmetal.
33) Main-group elements tend to form ions that have the same number of total electrons as the
nearest halogen.
34) A cation forms when an atom gains an electron.
35) Halogens form anions with a 1- charge.
36) Isotopes are atoms of the same element that have a different numbers of neutrons.
37) The atomic mass of individual atoms of an element may vary.
38) The relative amount of each different isotope in a naturally occurring sample of an element is
always the same.
39) All elements have three or more naturally occurring isotopes.
40) The atomic mass of a single carbon atom is equal to exactly 12.011 amu.
Multiple Choice Questions
1) Which of the following statements about atoms is FALSE?
A) Atoms compose all matter.
B) Atoms are responsible for the sensation of smell.
C) Atoms are the basic building block of nature.
D) An atom is the smallest identifiable unit of an element.
E) All of the above statements are true.
2) Which statement below accurately describes the contributions of Democritus?
A) ancient Greek philosopher who proposed that matter was not continuous
B) created the modern periodic table
C) proposed the modern Atomic Theory
D) discovered the existence of electrons
E) none of the above
3) Which statement below accurately describes the contributions of Dalton?
A) ancient Greek philosopher who proposed that matter was continuous
B) created the modern periodic table
C) proposed the modern Atomic Theory
D) discovered the existence of electrons
E) none of the above
4) Which of the following is NOT part of Dalton’s Atomic Theory?
A) Each element is composed of tiny indestructible particles called atoms.
B) All atoms of a given element have the same mass and other properties that distinguish them
from the atoms of other elements.
C) Atoms combine in simple, whole-number ratios to form compounds.
D) Most of the atom’s mass and all of its positive charge is contained in a small core called the
nucleus.
E) All of the above are part of the atomic theory.
5) Which statement below accurately describes the contributions of Thomson?
A) ancient Greek philosopher who proposed that matter was continuous
B) created the modern periodic table
C) proposed the modern Atomic Theory
D) discovered the existence of electrons
E) none of the above
6) Which of the statements about the discovery of electrons is FALSE?
A) Because atoms are neutral, the existence of a negatively charged particle implied there must
be a positively charged component of an atom.
B) Thomson proposed that electrons were small particles held within a positively charged sphere.
C) Rutherford proved the plum-pudding model correct.
D) The negatively charged electron is located outside the nucleus.
E) All of the above statements are true.
7) Which statement below is NOT consistent with the nuclear theory of the atom as proposed by
Rutherford?
A) Most of the atom’s mass and all of its positive charge is contained in a small core called the
nucleus.
B) Electrical charge is a fundamental property of protons and electrons in which like charges
repel and opposite charges attract.
C) Most of the volume of the atom is empty space occupied by tiny, negatively charged
electrons.
D) There are as many electrons outside the nucleus as there are protons inside the nucleus in a
neutral atom.
E) All of the above statements are consistent.
8) Which statement reflects the results of Rutherford’s gold foil experiments?
A) Almost all of the alpha particles were deflected back in the direction from which they came.
B) Almost all of the alpha particles sputtered gold atoms off of the surface of the foil.
C) Almost all of the alpha particles were deflected while passing through the foil.
D) Almost all of the alpha particles passed directly through the foil.
E) none of the above
9) An atom containing 7 protons, 8 neutrons, and 7 electrons:
A) is charge-neutral.
B) is an ion.
C) is an oxygen atom.
D) cannot exist.
E) none of the above
10) The atomic mass unit is defined as:
A) the mass of the hydrogen atom containing only one proton.
B) the mass of electrons found in a carbon atom containing six protons and neutrons.
C) 1/12 the mass of a carbon atom containing six protons and six neutrons.
D) 1/14 the mass of a nitrogen atom containing 7 protons and 7 neutrons.
E) none of the above
11) Which of the following statements about the nature of electrical charge is FALSE?
A) Electrical charge is a fundamental property of protons and electrons.
B) Positive and negative electrical charges attract each other.
C) Positive-positive or negative-negative charges repel each other.
D) Positive and negative charges cancel each other so that a proton and electron, when paired,
are charge neutral.
E) All of the above statements are true.
12) Which of the following subatomic particles has a mass of 1.67 × 10-27 kg?
A) electrons only
B) protons only
C) neutrons only
D) protons and neutrons
E) none of the above
13) Which of the following elements has an atomic number of 4?
A) H
B) C
C) He
D) Be
E) none of the above
14) Which of the following elements has only 12 protons?
A) C
B) Zn
C) Mg
D) O
E) none of the above
15) What is the atomic symbol for silver?
A) S
B) Ag
C) Au
D) Si
E) none of the above
16) What is the atomic symbol for tin?
A) Sn
B) Ti
C) Tn
D) Si
E) none of the above
17) What is the correct chemical symbol for mercury?
A) Hm
B) Hy
C) Me
D) My
E) none of the above
18) Which of the following is NOT a correct name, symbol combination?
A) beryllium, Be
B) magnesium, Mg
C) iron, I
D) manganese, Mn
E) silicon, Si
19) Which of the following is NOT a correct name, symbol combination?
A) beryllium, Be
B) phosphorus, P
C) iron, Fe
D) manganese, Mg
E) silicon, Si
20) Which of the following is NOT a correct name, symbol combination?
A) calcium, Ca
B) gold, Au
C) manganese, Mn
D) chromium, Cr
E) potassium, P
21) The names of the elements whose symbols are Si, P, Mn, and S are respectively:
A) silicon, potassium, magnesium, and sulfur.
B) silver, phosphorus, magnesium, and sulfur.
C) silicon, phosphorus, manganese, and sulfur.
D) silicon, phosphorus, magnesium, and sulfur.
E) silicon, potassium, magnesium, and sodium.
22) Which one of the following is a main-group element?
A) Ce
B) Co
C) Cu
D) Cs
E) none of the above
23) Metals are located where on the periodic table?
A) left side
B) right side
C) middle
D) zig-zag diagonal line
E) none of the above
24) Nonmetals are located where on the periodic table?
A) left side
B) right side
C) middle
D) zig-zag diagonal line
E) none of the above
25) Metalloids are located where on the periodic table?
A) left side
B) right side
C) middle
D) zig-zag diagonal line
E) none of the above
26) Group 1A elements are also called:
A) noble gases.
B) halogens.
C) alkaline earth metals.
D) alkali metals.
E) none of the above
27) Group 7A elements are also called:
A) noble gases.
B) halogens.
C) alkaline earth metals.
D) alkali metals.
E) none of the above
28) Group 8A elements are also called:
A) noble gases.
B) halogens.
C) alkaline earth metals.
D) alkali metals.
E) none of the above
29) Group 2A elements are also called:
A) noble gases.
B) halogens.
C) alkaline earth metals.
D) alkali metals.
E) none of the above
30) Mg is a member of which family?
A) noble gases
B) halogens
C) alkaline earth metals
D) alkali metals
E) none of the above
31) Xe is a member of which family?
A) noble gases
B) halogens
C) alkaline earth metals
D) alkali metals
E) none of the above